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    <meta charset="UTF-8">
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    <title>JavaScript 语句</title>
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<body>
    <h2>JavaScript语句</h2>
    <p><b>JavaScript程序</b>是一系列由计算机执行的<b>语句</b></p>
    <p id="demo"></p>
    <script>
        var x, y, z  //  语句1
        x = 22;   //  语句2
        y = 11;   //  语句3
        z = x + y;  //语句4
        document.getElementById("demo").innerHTML =
            "z 的值是" + z + "。";

    </script>
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